Rethreader



Jah. 24, E, E, DYSON ET AL i RETI-[READER Filed Nov. lO, 1944 Jinglll BVM 'l AT RNEY.

vili* v A-\\\\\\\\\\\\\\\\\ Patented Jan. 24, 1950 UNITED STATES PATENT OFFICE RETHREADER Eugene E. Dyson and William H. McCormick, New Britain, Conn.

f Application November 19, 1944, Serial No. 562,862 Z Claims. (Cl. 10121) Our invention relates to the class of devices which are employed for repairing a mutilated thread as on a shaft or `axle of considerable size particularly as found in heavy duty vehicles largely employed at the present time, and an object of our invention, among others, is the production of a device by the use of which such and in the construction and use of which the 'objects herein set out, as well as others, may

be attained is illustrated in the accompanying drawing, in which:

Figure 1 is a face view of our improved rethreading tool with parts broken away and shown in section.

Figure 2 is an edge view of the same partly in section.

Figure 3 is an end view of one of the steadying units.

Figure 4 is an end view of a rethreading unit.

Figures 5 and 6 are enlarged end views in cross section showing the nature of shafts requiring to be rethreaded.

In the accompanying drawings the numeral 6 denotes the body of our rethreading tool which is in the form of a ring of substantial thickness and width to sustain the threading and supporting units which are employed in thread reforming operations. This tool or instrument is for manual operation which is required in the rethreading of devices for which the instrument is made, the reforming of the threads on such dew'ces requiring care and close attention. Handles 'I are secured to and project from the edge of the body preferably on diametrically opposite sides.

Riders or steadying units 8 are supported in the body preferably at equal distances apart, iive being shown in the drawing herein, and a threading unit 9 is also supported in the body preferably at an equal distance from and between two of the steadying units, as shown in Fig. 1. The threading unit 9 is located preferably midway between the handles, although this is not absolutely essential but goes to make up a balanced structure.

The threading unit 9 comprises a sleeve support I0 that is fitted into and extends through the body, as shown in Fig. 1. A die holder II is located in the support I0 and is adjustably movable lengthwise therein, being held against rotating movement by means of a key I2 extending through the holder into a key groove I3 in 2 the holder. A feed screw I4 is threaded through a feed screw support I5 fastened in the end of the sleeve support IU, the feed screw having an annular groove at its inner end engaged by a retaining pin I 6 extending through the holder II into said groove, as shown in Fig. 2.

A thread cutting die I1 is secured to the end of the holder II as by means of a die retaining screw I 8 as shown in Fig. 4.

The riders or steadyng units 8 are of subst-antally the same construction as that just described with respect to the threading die, as to the supports, adjustable features, etc. A rider I9 is secured to the end of each of the rider supports 2U as by means of a retaining screw 2| as shown in Fig. 3.

These riders I9 are composed of a metal or substance which is comparatively soft so that it will not mutilate a thread which is formed on the threaded device being operated upon.

It will be noted that our improved rethreading tool includes a plurality of circumferentially spaced supports, such as the riders I9, and the threading dies, such as the die I'I, of which there are preferably live supports and one threading die that are evenly spaced, circumferentially, so that the said supports will engage the threaded surface and support the threading die in its position with relation to the surface of the member being threaded.

In use, our rethreading tool is first placed over the threaded portion of the member to be rethreaded, and the threading die II is moved into engagement with a good portion of the thread on said member. The riders I9 are then adjusted by being brought into contact with the threaded surface and, if necessary, the threading die I1 may be further adjusted for proper engagement with the thread.

Since the riders I9 are constructed of a soft metal which will not damage the threads, they may be forced into engagement with the threads, by means of t-he screws I4, so that the said threads will bite into the riders and thereby provide threads on the said riders in engagement with the threads on the member which will permit the tool to be carried along the threaded portion of the member with the rethreading die always supported in its adjusted position relatively to the said thread regardless of whether it is in contact with the thread or passing over a slot, such-as 22, or a at surface, such as 23.

Rotation of the tool upon the threaded portion will thus carry the threading die I'I through or rider relatively to the thread, or of said tool i upon the member.

Each of the sleevesupports l0 .'for"both;the'" rider and threading units has positioningv'avities 25 for the receptionpfthe inner ends vof positioning thumb screws`26. thesebeing for the placing of the units in such positions lasy maybe desired, the final adustments of the die and riders Abeing 'by'fmeans' ofv thefeed screws I4.

fWe claim:

1. rethreading 'tool-comprising a body 'naving an opening therein-adapted to receive a *'#memberf to 'be threaded, a single rethreading die extending radiallyfrom-said body into said open- A`ingffor-the purpose of rethreading a mutilated -threa'dfon said member, anda plurality of radial supports carried byfsaid body and formed of -`relativelyfsoft metal-adapted to engage the sur A-faceof said'member andhaving the threads of 1 said member cut threads' therein, and carry the l's'a'id rethreading die in 'adjusted position relatively to the thread onl said' member.

2. A y:rethreading tool 3of the character de-:

scribed in the form of a\body with 'an opening #therein adapted-to `receive'afmember to be rethreaded, a rethreading die extending into said opening and adapted to be adjusted into engagement with said thread, a plurality of supporting members extending into said opening and radially spaced about the axis of said member over a major portion of the circumferential distance thereof; the said carrying members being constructed of a soft material to thereby a*prevent damage to thef'threadsf'ofsaid' member and have Ithreads formed-therein for carrying the said rethreading die through said thread and across open spaces therein.

WILLIAM H. MCCORMICK.

EUGENE E. DYSON.

" REFERENCES CITED lThe following references are of record in the le of this patent:

UNITED STATES PATENTS 

